关于C++指针引用基础知识

　　1) 将引用作为参数

　　

#include<iostream>
using namespace std;

void  Log(int& as, int& bn);　　// 将参数设置引用.

int main()
{
    int xs = 100, ys = 620;
    cout << "initall a (xs) for: " << xs << " and (ys) for: " 
                　  << ys << endl;

    Log(xs, ys);
    cout << "uppdated (xs) for: " << xs 
         << " and (ys) for: " << ys <<endl;

    return 0;   
}

void Log(int& ap, int& bp)
{
    int temp = ap;    　　  // 传入 ap 的地址.
    　　ap = bp;　　　　　// bp 地址传入 ap. 
    bp = temp;　　　　// 即temp = ap = bp.
}

 

　　2）引用作为返回值

 

#include<iostream>
using namespace std;
double vlas_array[] = { 10.2, 32,3, 40,2 ,81,9, 30.0 };    

　double& Pointer_cite(int i); 　　// double类型函数定义引用.

int main()
{
// 引用前：

    cout << "No have by cite a array for: " << endl;
    for (int k = 0; k < 5; k++)
    {    
        cout << "vlas_array[" << k << "]: "
            << vlas_array[k] << endl;;
    }
    cout << "\n\n\n";

// 引用后:

    Pointer_cite(1) = 53.6;        // 修改索引内容值.
    Pointer_cite(4) = 100.2;    　

    cout << "No have by cite a array for: " << endl;
    for (int k = 0; k < 5; k++)
    {
        cout << "vlas_array[" << k << "]: "
            << vlas_array[k] << endl;
    }

    return 0;
}

double& Pointer_cite(int i)
{
    double& vaf = vlas_array[i];    // 同理引用数组索引内容.
    return vaf;　　　　　　
}